1
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Altarejos J, Valero A, Manzano R, Carreras J. Synthesis of Tri‐ and Tetrasubstituted Alkenyl Boronates from Alkynes. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Julia Altarejos
- Universidad de Alcalá Facultad de Ciencias: Universidad de Alcala Facultad de Ciencias Química Orgánica y Química Inorgánica SPAIN
| | - Antonio Valero
- Universidad de Alcalá Facultad de Ciencias: Universidad de Alcala Facultad de Ciencias Química Orgánica y Química Inorgánica SPAIN
| | - Rubén Manzano
- Universidad de Alcalá Facultad de Ciencias: Universidad de Alcala Facultad de Ciencias Química Orgánica y Química Inorgánica SPAIN
| | - Javier Carreras
- Universidad de Alcalá Facultad de Ciencias: Universidad de Alcala Facultad de Ciencias Química Orgánica y Química Inorgánica Carretera Madrid-Barcelona km 33,6, Campus Universitario.Facultad de Farmacia 28805 Alcalá de Henares SPAIN
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2
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Yang W, Krantz KE, Freeman LA, Dickie DA, Molino A, Kaur A, Wilson DJD, Gilliard RJ. Stable Borepinium and Borafluorenium Heterocycles: A Reversible Thermochromic "Switch" Based on Boron-Oxygen Interactions. Chemistry 2019; 25:12512-12516. [PMID: 31334883 DOI: 10.1002/chem.201903348] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Indexed: 12/13/2022]
Abstract
The first examples of N-heterocyclic carbene (NHC) and cyclic(alkyl)(amino) carbene (CAAC) stabilized borepinium and borafluorenium heterocycles are reported herein. The optical properties of the heterocyclic borenium cations were tuned by varying the Lewis base and by changing the number of atoms in the ring. More importantly, functionalizing the cationic boron ring system in the NHC-borafluorenium cation affords a temperature-sensitive molecule with reversible colorimetric "turn off/turn on" properties in solution. Notably, this is the first report of thermochromism in these cationic species. This property, which is mediated by an intermolecular boron-oxygen bond equilibrium, was examined in detail by X-ray crystallography, variable temperature-UV/Vis absorption spectroscopy (VT-UV/Vis), and density functional theory (DFT).
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Affiliation(s)
- Wenlong Yang
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Kelsie E Krantz
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Lucas A Freeman
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
| | - Andrew Molino
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Aishvaryadeep Kaur
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - David J D Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA
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3
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Wang D, Xue X, Houk KN, Shi Z. Mild Ring‐Opening 1,3‐Hydroborations of Non‐Activated Cyclopropanes. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201811036] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Di Wang
- State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 China
| | - Xiao‐Song Xue
- Department of Chemistry and BiochemistryUniversity of California Los Angeles CA 90095 USA
- State Key Laboratory of Elemento-organic ChemistryCollege of ChemistryNankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and BiochemistryUniversity of California Los Angeles CA 90095 USA
| | - Zhuangzhi Shi
- State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 China
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4
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Wang D, Xue X, Houk KN, Shi Z. Mild Ring‐Opening 1,3‐Hydroborations of Non‐Activated Cyclopropanes. Angew Chem Int Ed Engl 2018; 57:16861-16865. [DOI: 10.1002/anie.201811036] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Di Wang
- State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 China
| | - Xiao‐Song Xue
- Department of Chemistry and BiochemistryUniversity of California Los Angeles CA 90095 USA
- State Key Laboratory of Elemento-organic ChemistryCollege of ChemistryNankai University Tianjin 300071 China
| | - Kendall N. Houk
- Department of Chemistry and BiochemistryUniversity of California Los Angeles CA 90095 USA
| | - Zhuangzhi Shi
- State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 China
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5
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Franz D, Inoue S. Cationic Complexes of Boron and Aluminum: An Early 21st Century Viewpoint. Chemistry 2018; 25:2898-2926. [PMID: 30113744 DOI: 10.1002/chem.201803370] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Indexed: 01/03/2023]
Abstract
Boron and aluminum are lighter Group 13 elements, found in daily life commodities, and considered environmentally benign. Nevertheless, they markedly differ in their elemental properties (e.g., metal character, atomic radius). The use of Lewis acidic complexes of boron and aluminum for methods of bond activation and catalysis (e.g., hydrogenation of unsaturated substrates, polymerization of olefins and epoxides) is quickly expanding. The introduction of cationic charge may boost the metalloid-centered Lewis acidity and allow for its fine-tuning particularly with regard to preference for "hard" or "soft" Lewis bases (i.e., substrates). Especially the isolation of low-coordinate cations (number of ligand atoms smaller than four) demands elaborate techniques of thermodynamic and kinetic stabilization (i.e., electronic saturation and steric shielding) by a ligand system. Furthermore, the properties of the solvent and the counteranion must be considered with care. Here, selected examples of boron and aluminum cations are described.
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Affiliation(s)
- Daniel Franz
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748, Garching bei München, Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748, Garching bei München, Germany
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6
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7
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Heinrich M, Murphy JJ, Ilg MK, Letort A, Flasz J, Philipps P, Fürstner A. Total Synthesis of Putative Chagosensine. Angew Chem Int Ed Engl 2018; 57:13575-13581. [PMID: 30152031 DOI: 10.1002/anie.201808937] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Indexed: 12/22/2022]
Abstract
The marine macrolide chagosensine is the only natural product known to date that embodies a Z,Z-configured chloro-1,3-diene unit. This distinguishing substructure was prepared by a sequence of palladium-catalyzed 1,2-distannation of an alkyne precursor, regioselective Stille cross-coupling at the terminus of the resulting bisstannyl alkene with an elaborated alkenyl iodide, followed by chloro-destannation of the remaining internal site. The preparation of the required substrates centered on cobalt-catalyzed oxidative cyclization reactions of hydroxylated olefin precursors, which allowed the 2,5-trans-disubstituted tetrahydrofuran rings, embedded into each building block, to be formed with excellent selectivity. The highly strained macrolactone could ultimately be closed under forcing Yamaguchi conditions. Comparison of the spectral data of the synthetic sample with those of authentic chagosensine methyl ester confirmed that the structure of this intriguing compound has been mis-assigned by the isolation team.
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Affiliation(s)
- Marc Heinrich
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - John J Murphy
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Marina K Ilg
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Aurélien Letort
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Jakub Flasz
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Petra Philipps
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
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8
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Lv J, Zhao B, Liu L, Han Y, Yuan Y, Shi Z. Boron Trichloride‐Mediated Synthesis of Indoles
via
the Aminoboration of Alkynes. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201800509] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Jiahang Lv
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
| | - Binlin Zhao
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
| | - Li Liu
- Jiangsu Key Laboratory of Advanced Catalytic Materials and TechnologyChangzhou University Changzhou 213164 People's Republic of China
| | - Ying Han
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
| | - Yu Yuan
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
| | - Zhuangzhi Shi
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
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9
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Ueno A, Li J, Daniliuc CG, Kehr G, Erker G. Metal-Free Acetylene Coupling by the (C 6 F 5 ) 2 B-X 1,2-Halogenoboration Reaction. Chemistry 2018; 24:10044-10048. [PMID: 29722929 DOI: 10.1002/chem.201802084] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Indexed: 01/24/2023]
Abstract
(C6 F5 )2 B-halides were conveniently prepared by treatment of (C6 F5 )2 BH with tritylchloride or -bromide, respectively. With cyclopropylacetylene, (C6 F5 )2 BBr underwent sequential cis-1,2-halogenoboration followed by 1,2-carboboration to give the 4-bromo-2,4-dicyclopropylbutadienyl-B(C6 F5 )2 product. It reacted further with additional cyclopropylacetylene to give the linear triene and tetraene products in a metal-free alkyne oligomerization reaction. The pyridine adduct of the initial diene product was characterized by X-ray diffraction. (C6 F5 )2 BCl reacted analogously. Similar (C6 F5 )2 BX induced oligomerization reactions were carried out with two conjugated enynes.
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Affiliation(s)
- Atsushi Ueno
- Organisch-Chemisches Institut der Universität Münster, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany
| | - Jun Li
- Organisch-Chemisches Institut der Universität Münster, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut der Universität Münster, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut der Universität Münster, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut der Universität Münster, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, 48149, Münster, Germany
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10
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Wilkins LC, Soltani Y, Lawson JR, Slater B, Melen RL. Divergent Elementoboration: 1,3-Haloboration versus 1,1-Carboboration of Propargyl Esters. Chemistry 2018; 24:7364-7368. [PMID: 29700863 PMCID: PMC6055811 DOI: 10.1002/chem.201801493] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Indexed: 01/03/2023]
Abstract
This work showcases the 1,3-haloboration reaction of alkynes in which boron and chlorine add to propargyl systems in a proposed sequential oxazoliumborate formation with subsequent ring-opening and chloride migration. In addition, the functionalization of these propargyl esters with dimethyl groups in the propargylic position leads to stark differences in reactivity whereby a formal 1,1-carboboration prevails to give the 2,2-dichloro-3,4-dihydrodioxaborinine products as an intramolecular chelate. Density functional theory calculations are used to rationalize the distinct carboboration and haloboration pathways. Significantly, this method represents a metal-free route to highly functionalized compounds in a single step to give structurally complex products.
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Affiliation(s)
- Lewis C Wilkins
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Yashar Soltani
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - James R Lawson
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Ben Slater
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Rebecca L Melen
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
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11
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Franz D, Szilvási T, Pöthig A, Deiser F, Inoue S. Three-Coordinate Boron(III) and Diboron(II) Dications. Chemistry 2018; 24:4283-4288. [DOI: 10.1002/chem.201800609] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Daniel Franz
- Department of Chemistry, Catalysis Research Center; Institute of Silicon Chemistry; Technische Universität München; Lichtenbergstr. 4 85748 Garching bei München Germany
| | - Tibor Szilvási
- Department of Chemical and Biological Engineering; University of Wisconsin-Madison; 1415 Engineering Drive Madison WI 53706-1607 USA
| | - Alexander Pöthig
- Department of Chemistry, Catalysis Research Center; Institute of Silicon Chemistry; Technische Universität München; Lichtenbergstr. 4 85748 Garching bei München Germany
| | - Franziska Deiser
- Department of Chemistry, Catalysis Research Center; Institute of Silicon Chemistry; Technische Universität München; Lichtenbergstr. 4 85748 Garching bei München Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, Catalysis Research Center; Institute of Silicon Chemistry; Technische Universität München; Lichtenbergstr. 4 85748 Garching bei München Germany
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12
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Geier SJ, Vogels CM, Mellonie NR, Daley EN, Decken A, Doherty S, Westcott SA. The Phosphinoboration ofN-Heterocycles. Chemistry 2017; 23:14485-14499. [DOI: 10.1002/chem.201702203] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Indexed: 01/08/2023]
Affiliation(s)
- Stephen J. Geier
- Department of Chemistry and Biochemistry; Mount Allison University; Sackville NB E4L 1G8 Canada
| | - Christopher M. Vogels
- Department of Chemistry and Biochemistry; Mount Allison University; Sackville NB E4L 1G8 Canada
| | - Niall R. Mellonie
- NUCAT, School of Chemistry, Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU England
| | - Erika N. Daley
- Department of Chemistry and Biochemistry; Mount Allison University; Sackville NB E4L 1G8 Canada
| | - Andreas Decken
- Department of Chemistry; University of New Brunswick; Fredericton NB E3B 5A3 Canada
| | - Simon Doherty
- NUCAT, School of Chemistry, Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU England
| | - Stephen A. Westcott
- Department of Chemistry and Biochemistry; Mount Allison University; Sackville NB E4L 1G8 Canada
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13
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Scherpf T, Feichtner K, Gessner VH. Using Ylide Functionalization to Stabilize Boron Cations. Angew Chem Int Ed Engl 2017; 56:3275-3279. [PMID: 28185370 PMCID: PMC5363341 DOI: 10.1002/anie.201611677] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/26/2017] [Indexed: 11/17/2022]
Abstract
The metalated ylide YNa [Y=(Ph3 PCSO2 Tol)- ] was employed as X,L-donor ligand for the preparation of a series of boron cations. Treatment of the bis-ylide functionalized borane Y2 BH with different trityl salts or B(C6 F5 )3 for hydride abstraction readily results in the formation of the bis-ylide functionalized boron cation [Y-B-Y]+ (2). The high donor capacity of the ylide ligands allowed the isolation of the cationic species and its characterization in solution as well as in solid state. DFT calculations demonstrate that the cation is efficiently stabilized through electrostatic effects as well as π-donation from the ylide ligands, which results in its high stability. Despite the high stability of 2 [Y-B-Y]+ serves as viable source for the preparation of further borenium cations of type Y2 B+ ←LB by addition of Lewis bases such as amines and amides. Primary and secondary amines react to tris(amino)boranes via N-H activation across the B-C bond.
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Affiliation(s)
- Thorsten Scherpf
- Chair of Inorganic Chemistry IIFaculty of Chemistry and BiochemistryRuhr University BochumUniversitätsstraße 15044780BochumGermany
| | - Kai‐Stephan Feichtner
- Chair of Inorganic Chemistry IIFaculty of Chemistry and BiochemistryRuhr University BochumUniversitätsstraße 15044780BochumGermany
| | - Viktoria H. Gessner
- Chair of Inorganic Chemistry IIFaculty of Chemistry and BiochemistryRuhr University BochumUniversitätsstraße 15044780BochumGermany
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14
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Scherpf T, Feichtner KS, Gessner VH. Using Ylide Functionalization to Stabilize Boron Cations. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611677] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Thorsten Scherpf
- Chair of Inorganic Chemistry II; Faculty of Chemistry and Biochemistry; Ruhr University Bochum; Universitätsstraße 150 44780 Bochum Germany
| | - Kai-Stephan Feichtner
- Chair of Inorganic Chemistry II; Faculty of Chemistry and Biochemistry; Ruhr University Bochum; Universitätsstraße 150 44780 Bochum Germany
| | - Viktoria H. Gessner
- Chair of Inorganic Chemistry II; Faculty of Chemistry and Biochemistry; Ruhr University Bochum; Universitätsstraße 150 44780 Bochum Germany
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15
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Faizi DJ, Davis AJ, Meany FB, Blum SA. Catalyst-Free Formal Thioboration to Synthesize Borylated Benzothiophenes and Dihydrothiophenes. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608090] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Darius J. Faizi
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| | - Ashlee J. Davis
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| | - Fiach B. Meany
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
| | - Suzanne A. Blum
- Department of Chemistry; University of California, Irvine; Irvine CA 92697 USA
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16
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Faizi DJ, Davis AJ, Meany FB, Blum SA. Catalyst-Free Formal Thioboration to Synthesize Borylated Benzothiophenes and Dihydrothiophenes. Angew Chem Int Ed Engl 2016; 55:14286-14290. [PMID: 27735114 DOI: 10.1002/anie.201608090] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/22/2016] [Indexed: 12/30/2022]
Abstract
The first ring-forming thioboration reaction of C-C π bonds is reported. This catalyst-free method proceeds in the presence of a commercially available external electrophilic boron source (B-chlorocatecholborane) in good to high yields. The method is scalable and tolerates a variety of functional groups that are intolerant of other major borylation methods. The resulting borylated benzothiophenes participate in a variety of in situ derivatization reactions, showcasing that these borylated intermediates do not need to be isolated prior to downstream functionalization. This methodology has been extended to the synthesis of borylated dihydrothiophenes. Mechanistic experiments suggest that the operative mechanistic pathway is through boron-induced activation of the alkyne followed by electrophilic cyclization, as opposed to S-B σ bond formation, providing a mechanistically distinct pathway to the thioboration of C-C π bonds.
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Affiliation(s)
- Darius J Faizi
- Department of Chemistry, University of California, Irvine, Irvine, CA, 92697, USA
| | - Ashlee J Davis
- Department of Chemistry, University of California, Irvine, Irvine, CA, 92697, USA
| | - Fiach B Meany
- Department of Chemistry, University of California, Irvine, Irvine, CA, 92697, USA
| | - Suzanne A Blum
- Department of Chemistry, University of California, Irvine, Irvine, CA, 92697, USA.
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17
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Wilkins LC, Lawson JR, Wieneke P, Rominger F, Hashmi ASK, Hansmann MM, Melen RL. The Propargyl Rearrangement to Functionalised Allyl-Boron and Borocation Compounds. Chemistry 2016; 22:14618-24. [PMID: 27538742 DOI: 10.1002/chem.201602719] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Indexed: 11/08/2022]
Abstract
A diverse range of Lewis acidic alkyl, vinyl and aryl boranes and borenium compounds that are capable of new carbon-carbon bond formation through selective migratory group transfer have been synthesised. Utilising a series of heteroleptic boranes [PhB(C6 F5 )2 (1), PhCH2 CH2 B(C6 F5 )2 (2), and E-B(C6 F5 )2 (C6 F5 )C=C(I)R (R=Ph 3 a, nBu 3 b)] and borenium cations [phenylquinolatoborenium cation ([QOBPh][AlCl4 ], 4)], it has been shown that these boron-based compounds are capable of producing novel allyl- boron and boronium compounds through complex rearrangement reactions with various propargyl esters and carbamates. These reactions yield highly functionalised, synthetically useful boron substituted organic compounds with substantial molecular complexity in a one-pot reaction.
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Affiliation(s)
- Lewis C Wilkins
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - James R Lawson
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Philipp Wieneke
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - A Stephen K Hashmi
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.,Chemistry Department, Faculty of Science, King Abdulaziz University (KAU), Jeddah, 21589, Saudi Arabia
| | - Max M Hansmann
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Rebecca L Melen
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK.
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18
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Longobardi LE, Johnstone TC, Falconer RL, Russell CA, Stephan DW. Hydroboration of Phosphaalkynes by HB(C6F5)2. Chemistry 2016; 22:12665-9. [DOI: 10.1002/chem.201602860] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Lauren E. Longobardi
- Department of Chemistry; University of Toronto; 80 St. George St Toronto ON M5S 3H6 Canada
| | - Timothy C. Johnstone
- Department of Chemistry; University of Toronto; 80 St. George St Toronto ON M5S 3H6 Canada
| | - Rosalyn L. Falconer
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | | | - Douglas W. Stephan
- Department of Chemistry; University of Toronto; 80 St. George St Toronto ON M5S 3H6 Canada
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19
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Jaiswal K, Prashanth B, Singh S. Fine-Tuning of Lewis Acidity: The Case of Borenium Hydride Complexes Derived from Bis(phosphinimino)amide Boron Precursors. Chemistry 2016; 22:11035-41. [PMID: 27351275 DOI: 10.1002/chem.201600382] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Indexed: 11/11/2022]
Abstract
Reactions of bis(phosphinimino)amines LH and L'H with Me2 S⋅BH2 Cl afforded chloroborane complexes LBHCl (1) and L'BHCl (2), and the reaction of L'H with BH3 ⋅Me2 S gave a dihydridoborane complex L'BH2 (3) (LH=[{(2,4,6-Me3 C6 H2 N)P(Ph2 )}2 N]H and L'H=[{(2,6-iPr2 C6 H3 N)P(Ph2 )}2 N]H). Furthermore, abstraction of a hydride ion from L'BH2 (3) and LBH2 (4) mediated by Lewis acid B(C6 F5 )3 or the weakly coordinating ion pair [Ph3 C][B(C6 F5 )4 ] smoothly yielded a series of borenium hydride cations: [L'BH](+) [HB(C6 F5 )3 ](-) (5), [L'BH](+) [B(C6 F5 )4 ](-) (6), [LBH](+) [HB(C6 F5 )3 ](-) (7), and [LBH](+) [B(C6 F5 )4 ](-) (8). Synthesis of a chloroborenium species [LBCl](+) [BCl4 ](-) (9) without involvement of a weakly coordinating anion was also demonstrated from a reaction of LBH2 (4) with three equivalents of BCl3 . It is clear from this study that the sterically bulky strong donor bis(phosphinimino)amide ligand plays a crucial role in facilitating the synthesis and stabilization of these three-coordinated cationic species of boron. Therefore, the present synthetic approach is not dependent on the requirement of weakly coordinating anions; even simple BCl4 (-) can act as a counteranion with borenium cations. The high Lewis acidity of the boron atom in complex 8 enables the formation of an adduct with 4-dimethylaminopyridine (DMAP), [LBH⋅(DMAP)](+) [B(C6 F5 )4 ](-) (10). The solid-state structures of complexes 1, 5, and 9 were investigated by means of single-crystal X-ray structural analysis.
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Affiliation(s)
- Kuldeep Jaiswal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, 140306, Punjab, India
| | - Billa Prashanth
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, 140306, Punjab, India
| | - Sanjay Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, 140306, Punjab, India.
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Warner AJ, Lawson JR, Fasano V, Ingleson MJ. Formation of C(sp(2))-boronate esters by borylative cyclization of alkynes using BCl3. Angew Chem Int Ed Engl 2015; 54:11245-9. [PMID: 26237115 PMCID: PMC4832827 DOI: 10.1002/anie.201505810] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Indexed: 11/29/2022]
Abstract
BCl3 is an inexpensive electrophile which induces the borylative cyclization of a wide range of substituted alkynes to regioselectively form polycycles containing synthetically versatile C(sp(2) )boronate esters. It proceeds rapidly, with good yields and is compatible with a range of functional groups and substitution patterns. Intermolecular 1,2-carboboration of alkynes is also achieved using BCl3 to generate trisubstituted vinyl boronate esters.
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Affiliation(s)
- Andrew J Warner
- School of Chemistry, University of Manchester, Manchester, M13 9PL (UK)
| | - James R Lawson
- School of Chemistry, University of Manchester, Manchester, M13 9PL (UK)
| | - Valerio Fasano
- School of Chemistry, University of Manchester, Manchester, M13 9PL (UK)
| | - Michael J Ingleson
- School of Chemistry, University of Manchester, Manchester, M13 9PL (UK).
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Yoshimura A, Takamachi Y, Han L, Ogawa A. Organosulfide‐Catalyzed Diboration of Terminal Alkynes under Light. Chemistry 2015; 21:13930-3. [DOI: 10.1002/chem.201502425] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Aya Yoshimura
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1‐1 Gakuen‐cho, Nakaku, Sakai, Osaka 599‐8531 (Japan)
- National Institute of Advanced Industrial Science and Technology (AIST), 1‐1‐1, Higashi, Tsukuba, Ibaraki, 305‐8565 (Japan)
| | - Yuki Takamachi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1‐1 Gakuen‐cho, Nakaku, Sakai, Osaka 599‐8531 (Japan)
| | - Li‐Biao Han
- National Institute of Advanced Industrial Science and Technology (AIST), 1‐1‐1, Higashi, Tsukuba, Ibaraki, 305‐8565 (Japan)
| | - Akiya Ogawa
- Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1‐1 Gakuen‐cho, Nakaku, Sakai, Osaka 599‐8531 (Japan)
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Warner AJ, Lawson JR, Fasano V, Ingleson MJ. Formation of C(sp2)Boronate Esters by Borylative Cyclization of Alkynes Using BCl3. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201505810] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Farrell JM, Stephan DW. Planar N-Heterocyclic Carbene Diarylborenium Ions: Synthesis by Cationic Borylation and Reactivity with Lewis Bases. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500198] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Farrell JM, Stephan DW. Planar N-Heterocyclic Carbene Diarylborenium Ions: Synthesis by Cationic Borylation and Reactivity with Lewis Bases. Angew Chem Int Ed Engl 2015; 54:5214-7. [DOI: 10.1002/anie.201500198] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/02/2015] [Indexed: 11/05/2022]
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Eisenberger P, Bestvater BP, Keske EC, Crudden CM. Hydrogenations at Room Temperature and Atmospheric Pressure with Mesoionic Carbene-Stabilized Borenium Catalysts. Angew Chem Int Ed Engl 2015; 54:2467-71. [DOI: 10.1002/anie.201409250] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Indexed: 11/08/2022]
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Eisenberger P, Bestvater BP, Keske EC, Crudden CM. Hydrogenations at Room Temperature and Atmospheric Pressure with Mesoionic Carbene-Stabilized Borenium Catalysts. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201409250] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tsuchimoto T, Utsugi H, Sugiura T, Horio S. Alkynylboranes: A Practical Approach by Zinc-Catalyzed Dehydrogenative Coupling of Terminal Alkynes with 1,8-Naphthalenediaminatoborane. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400767] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Franz D, Irran E, Inoue S. Isolierung eines dreifach koordinierten Borkations mit einer Bor-Schwefel-Doppelbindung. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407809] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Franz D, Irran E, Inoue S. Isolation of a Three-Coordinate Boron Cation with a Boron-Sulfur Double Bond. Angew Chem Int Ed Engl 2014; 53:14264-8. [DOI: 10.1002/anie.201407809] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Indexed: 11/08/2022]
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Abstract
The reaction of 8-(trimethylsiloxy)quinoline (QOTMS) with BCl3 and
(aryl)BCl2 forms QOBCl2 and QOBCl(aryl). The subsequent addition
of stoichiometric AlCl3 follows one of two paths, dependent on the steric demands of the
QO ligand and the electrophilicity of the resulting borenium cation. The phenyl- and
5-hexylthienylborenium cations, QOBPh+ and
QOBTh+, are formed, whereas QOBCl+ is
not. Instead, AlCl3 preferentially binds with QOBCl2 at oxygen,
forming QOBCl2⋅AlCl3, rather than abstracting chloride. A
modest increase in the steric demands around oxygen, by installing a methyl group at the 7-position
of the quinolato ligand, switches the reactivity with AlCl3 back to chloride abstraction,
allowing formation of QOBCl+. All the
prepared borenium cations are highly chlorophilic and exhibit significant interaction with
AlCl4− resulting in an equilibrium concentration of Lewis acidic
“AlCl3” species. The presence of
“AlCl3” species limits the alkyne substrates compatible with
these borenium systems, with reaction of
[QOBPh][AlCl4] with 1-pentyne exclusively
yielding the cyclotrimerised product, 1,3,5-tripropylbenzene. In contrast,
QOBPh+ and QOBTh+ systems effect the
syn-1,2-carboboration of 3-hexyne. DFT calculations at the
M06-2X/6-311G(d,p)/PCM(DCM) level confirm that the higher migratory aptitude of Ph versus Me leads
to a lower barrier to 1,2-carboboration relative to 1,1-carboboration.
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Affiliation(s)
- Ian A Cade
- School of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL (UK)
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Shen CT, Liu YH, Peng SM, Chiu CW. A Di-Substituted Boron Dication and Its Hydride-Induced Transformation to an NHC-Stabilized Borabenzene. Angew Chem Int Ed Engl 2013; 52:13293-7. [DOI: 10.1002/anie.201308385] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Indexed: 11/09/2022]
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Shen CT, Liu YH, Peng SM, Chiu CW. A Di-Substituted Boron Dication and Its Hydride-Induced Transformation to an NHC-Stabilized Borabenzene. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201308385] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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